On 18 April 1955, a group including Switzerland's Ernst Thommen, Italy's Ottorino Barassi, and England's Stanley Rous founded the Inter-Cities Fairs Cup, an annual football tournament for European club teams.
As reflected in its name, the tournament was designed originally to promote international trade fairs, with participation limited to teams from cities participating in such fairs. The rules limited each participating city to one team each.
Because the matches themselves were scheduled to coincide with the fairs, the tournament's first season ran for three years, from 1955 to 1958. That first season included teams from Barcelona, Basle, Birmingham, Cologne, Copenhagen, Frankfurt, Lausanne, Leipzig, London, Milan, Vienna, and Zagreb, with the team from Barcelona (consisting primarily of players from F.C. Barcelona, along with one player from R.C.D. Espanyol) claiming the first title.
In 1971, UEFA took control of the tournament and rebranded it as the UEFA Cup, with Leeds United winning the first UEFA Cup trophy.
Starting in the 2009-2010 season, the tournament will again be rebranded, this time as the Europa League.